Turnable hot top and lifting fork

ABSTRACT

A hot top having a one-piece casing lined with a heat insulating lining and having a single-use refractory bottom ring assembly secured to the bottom of the casing to support the lining. The casing is provided with an elliptical lifting lug integral with the outside surface of each of the side and end walls of the casing and a round turning trunnion integral with each of the lifting lugs. The casing is lifted by a lifting yoke having lifting surfaces corresponding to the surfaces of the lifting lugs.

United States Patent Inventor Donald C. Atkinson Ellwood City, Pa.

Appl. No. 865,937

Filed Oct. 13, 1969 Patented Oct. 12, 1971 Assignee Universal Refractories Corporation Milwaukee, Wis.

Continuation of application Ser. No. 9 9 591 tm tqo dn q- TURNABLE HOT TOP AND LIFIING FORK 4 Claims, 4 Drawing Figs.

US. Cl 249/202, 294/68 Int. Cl 8 2217/10 Field of Search 249/197-202, 106; 294/67 DC, 68, 69 R, 81 R, 82 R, 73

[56] References Cited UNITED STATES PATENTS 567,181 9/1896 Weldon 294/69 1,804,204 5/1931 Charman et a1. 249/202 X 3,239,187 3/1966 Daley 249/197 X Primary Examiner-Robert D, Baldwin Attorneys-Ronald E. Barry and James E. Nilles ABSTRACT: A hot top having a one-piece casing lined with a heat insulating lining and having a single-use refractory bottom ring assembly secured to the bottom of the casing to support the lining. The casing is provided with an elliptical lifting lug integral with the outside surface of each of the side and end walls of the casing and a round turning trunnion integral with each of the lifting lugs. The casing is lifted by a lifting yoke having lifting surfaces corresponding to the surfaces of the lifting lugs.

TURNABLE HOT TOP AND LIFI'ING FORK CROSS-REFERENCE TO RELATED APPLICATION This application is a continuation of my copending application Ser. No. 668,010, filed Sept. 15, 1967.

BACKGROUND OF THE INVENTION As ingot molds are teemed with molten metal, the sides of the mold are subjected to intense heat. The cumulative effect of this heat on the sides of the mold to the next mold often causes heat checking or cracking of the sides reducing the life of the ingot mold. Heat checking is a gradual deterioration of the metal in the walls of the mold due to repeated heating and cooling of the sides of the mold. The hot tops that are positioned on the top of the ingot mold are also'subject to the same cumulative heat effect. The hot tops are placed on the ingot mold and removed from the mold by a crane having a lifting fork that engages lifting lugs provided on two of the sides of the hot top. The crane which is used to place the hot top on the ingot mold moves in only one direction and the hot tops are, therefore, always placed in the same position on the ingot mold since there is only one set of lifting lugs on the hot top. Turning trunnions are provided on the other two sides of the hot top and are used to support the hot top when the hot top is inverted and new liners and bottom rings secured to the hot top. If the ingot molds could be turned periodically, the life of the ingot mold could be increased since the effects of heat checking would be distributed between all of the sides of the mold. This cannot be done in the present systems.

SUMMARY OF THE INVENTION This invention relates to an improved hot top and lifting fork which makes it possible to turn the hot top and place it on an ingot mold regardless of the position of the ingot mold. The hot top includes a one-piece casing having sidewalls and end walls with lifting lugs cast on the outer surface of each of the end walls and sidewalls. The turning trunnions which are used to support the casing are cast integral with the lifting lugs thereby allowing the hot top to be picked up from either direction. Since the lifting lugs are located in all four sides of the hot top, the hot top can be turned to correspond to the position of the ingot mold and picked up and placed in position. By turning the ingot mold and the hot top the life of both the mold and hot top can be prolonged. The lifting fork is provided with lifting surfaces which matingly engage corresponding surfaces on lifting lugs. These surfaces are made in an arcuate elliptical arc and when properly seated will prevent the hot top from tipping as it is lowered into the ingot mold.

Other objects and advantages will become more apparent from the following detailed description when read in connection with the accompanying drawings in which:

FIG. 1 is a perspective view of a hot top positioned on the top of the ingot mold.

FIG. 2 is a side view of the hot top.

FIG. 3 is a sectional view of the hot top.

FIG. 4 is a perspective view of the lifting yoke above the hot top.

Referring more particularly to the drawing, an ingot mold is shown with a hot top 12 positioned on the top of the ingot mold with the lower end of the hot top inserted into opening 15 in the mold. A pair of support blocks 14 are provided on each of the opposite sides of the hot top to engage the top of the ingot mold when the hot top is placed in position.

The hot top includes a one-piece casing having end walls 22 and sidewalls 24. The casings are made to the dimensions of the ingot molds on which they are to be used and are generally rectangular in shape although square-shaped hot tops are used with square ingot molds. A bottom ring assembly 26 having a refractory ring with a wiper strip 28 secured to the outer peripheral surfaces of the ring is secured to the hot top casing by clips 32. An insulating liner 30 is positioned flush with the inside surface of the hot top and is supported on the top of the bottom ring. The liner and bottom ring can be made of the same or similar refractory material or either or both can be made of insulating material. The liner can also be made in one piece and folded to fit into the hot top.

A lifting lug 40 is cast integral with the outer surface of each of the casing walls. Means are provided on the lugs 40 to prevent rotation of the casing 20 when transported to and from the ingot mold 10. Such means is in the form of an arcuate elliptical lifting surface 42 which has upwardly and outwardly diverging surfaces 43. A cylindrical turning trunnion 44 is cast integral with each of the lifting lugs with the axis of the turning trunnion coaxial with the center of the lower end of the lug 40. The lifting lug 40 and turning trunnion 44 on each side of the casing 20 is also coaxial with the lifting lug 40 and turning trunnion 44 located on the opposite sidewall of the casing 20. The axes of the oppositely disposed lifting lugs and turning trunnions pass through the center of gravity of the hot top 12 which can be assumed to be the same as the casing 20.

In the event the hot top has a rectangular shape wherein the sidewalls are longer than the end walls, a spacer 60 is cast in the sidewalls between the lifting lug andthe outer surface of the sidewall. The spacer should have a thickness equal to onehalf the difference between the length of the sidewall and the length of the end wall. The lifting lugs on the sidewall will then be spaced apart a distance equal to the distance between the lifting lugs on the end walls. A single lifting yoke 50 can then be used to lift the hot top regardless of which position it is in when it reaches the lifting yoke.

As seen in FIG. 4, the lifting yoke 50 is provided with means for preventing turning of the casing in the form of a pair of lifting arms 52 having arcuate elliptical surfaces 54 that slope upwardly and outwardly and correspond to the lifting surface 42. The yoke is brought up to matingly engage the lifting lugs by tilting the yoke until the ends 55 of the yoke fit under the lifting lug and then pulled sideways and upward until the yoke is vertical. This means that the distance between the ends 55 and the inner surface 57 of the yoke must be sufficient to clear the top and bottom of the lifting lug when the yoke is pulled into position. The lifting lugs will seat snugly in the lifting fork preventing any motion between the hot top and lugs. As the hot top is raised it will remain even with the floor and when the hot top is lowered into the top of the ingot mold there will be substantially little or no motion between the lifting fork and the hot top.

Although only one embodiment of the present invention has been shown and described,-it should be apparent that various changes and modifications can be made herein without departing from the scope of the appended claims.

What is claimed is:

l. The combination of a hot top and a lifting fork wherein said hot top includes a one-piece casing having end walls and sidewalls,

and a lifting lug on the outer surface of each of said end walls and said sidewalls and a turning trunnion on each of said lifting lugs,

said lifting lugs having arcuate ellipticallifting surfaces and said lifting fork includes lifting surfaces corresponding to said lifting surfaces on said lifting lugs.

2. The combination according to claim I wherein said hot top sidewalls are longer than the end walls,

said sidewalls including spacers cast between the lifting lugs and the outer surface of the sidewalls,

whereby the distance between the lifting lugs on the sidewalls will be the same as the distance between the lifting lugs on the end walls.

3. The combination of a hot top and a lifting fork wherein said hot top includes a casing having end walls and sidewalls,

a lifting lug having an elliptical configuration and being located on the outer surface of each end wall and each sidewall,

a turning trunnion on each lifting lug,

said turning trunnion and lifting lug on each wall being suba lifting lug on the outer surface of each end wall and each stantially coaxial with the turning trunnion and lifting lug sidewall, said lifting lug having upwardly and outwardly on the opposite wall, diverging lifting surfaces, the axes of all of said lifting lugs and turning trunnions intera cylindrical turning trunnion on each lifting lug,

e ting t ximatel the enter f it f id 5 said turning trunnion and said lifting lug on each wall being i and coaxial with each other and with the turning trunnion and said lifting fork including an elliptical configuration corlifting lug the pp responding to said fli lug f preventing rotation f said axes of said turning trunnions and said lifting lugs intersaid casing on engagement with said lifting lugs. secting at substantially the center of gravity of said casing,

4 The combination of a hot top and a lifting fork wherein l0 and said lifting fork including lifting surfaces corresponding said hot top includes to said lifting lug lifting surfaces.

a one-piece casing having end walls and sidewalls, 

1. The combination of a hoT top and a lifting fork wherein said hot top includes a one-piece casing having end walls and sidewalls, and a lifting lug on the outer surface of each of said end walls and said sidewalls and a turning trunnion on each of said lifting lugs, said lifting lugs having arcuate elliptical lifting surfaces and said lifting fork includes lifting surfaces corresponding to said lifting surfaces on said lifting lugs.
 2. The combination according to claim 1 wherein said hot top sidewalls are longer than the end walls, said sidewalls including spacers cast between the lifting lugs and the outer surface of the sidewalls, whereby the distance between the lifting lugs on the sidewalls will be the same as the distance between the lifting lugs on the end walls.
 3. The combination of a hot top and a lifting fork wherein said hot top includes a casing having end walls and sidewalls, a lifting lug having an elliptical configuration and being located on the outer surface of each end wall and each sidewall, a turning trunnion on each lifting lug, said turning trunnion and lifting lug on each wall being substantially coaxial with the turning trunnion and lifting lug on the opposite wall, the axes of all of said lifting lugs and turning trunnions intersecting at approximately the center of gravity of said casing, and said lifting fork including an elliptical configuration corresponding to said lifting lug for preventing rotation of said casing on engagement with said lifting lugs.
 4. The combination of a hot top and a lifting fork wherein said hot top includes a one-piece casing having end walls and sidewalls, a lifting lug on the outer surface of each end wall and each sidewall, said lifting lug having upwardly and outwardly diverging lifting surfaces, a cylindrical turning trunnion on each lifting lug, said turning trunnion and said lifting lug on each wall being coaxial with each other and with the turning trunnion and lifting lug on the opposite wall, said axes of said turning trunnions and said lifting lugs intersecting at substantially the center of gravity of said casing, and said lifting fork including lifting surfaces corresponding to said lifting lug lifting surfaces. 